In recent years, competition games have been made playable among a plurality of shops via a network. In game terminal devices of this type, game results are collected by a central server, ranking in the entire country, area or shop is calculated based on the game results of players, the calculated ranking is displayed in the game devices at the end of the game or various awards (virtual honors, ranks, grades, etc.) determined in the game are given. Participation in the game is urged by displaying the ranking of top scorers and giving awards in this way.
A player tries to get a good game result in each game because he desires to be ranked high even in games. However, if such desire increases, there is a possibility of such a player psychology as not to leave a game result disadvantage to himself since his ranking may be lowered if the game ends when he loses ground while playing the game. As a result, the player may try to prevent the transmission of the game result to a central server before the game thought to end up with an unfavorable result is normally ended.
For example, it is thought to prevent the transmission of the game result to a host by turning a power switch of the game device off or shutting a network cable off to forcibly end (unusual end) the game during the game in the shop. In the case of such hindrance to the transmission of the game result to the central server, the ranking of the player having done such an action is hardly lowered in the end. Accordingly, the game result is not correctly reflected on the ranking, making a fair ranking process or its display impossible, wherefore the ranking becomes unfair to honest players.
There can be also thought a method for monitoring an occurrence of unusual end and preventing the participation of a player having done many unusual ends in the game assuming that he is conducting an unauthorized operation. However, there is a certain limit in relating the number of unusual ends and true unauthorized operations.